Search for single vectorlike quarks in pp ̄ collisions at √s=1.96 TeV

We present a search for hypothetical vectorlike quarks in pp ̅ collisions at √s=1.96  TeV. The data were collected by the D0 detector at the Fermilab Tevatron Collider and correspond to an integrated luminosity of 5.4  fb(-1). We select events with a final state composed of a W or Z boson and a jet consistent with a heavy object decay. We observe no significant excess in comparison to the background prediction and set limits on production cross sections for vectorlike quarks decaying to W+jet and Z+jet. These are the most stringent limits to date for electroweak single vectorlike quark production at hadron colliders.

Clinical characteristics and molecular analysis of 21 Chinese children with congenital agammaglobulinemia

Congenital agammaglobulinemia is a humoral primary immunodeficiency and affected patients have extremely low levels of peripheral B cells and profound deficiency of all immunoglobulin isotypes. Mutations of the Bruton's tyrosine kinase (BTK) gene are responsible for most of the congenital agammaglobulinemia. In this study, the phenotypes of congenital agammaglobulinemia were investigated in 21 male children from 21 unrelated Chinese families. Sixteen different mutations of BTK gene were identified in 18 patients, and three patients did not have BTK gene mutations. Nine mutations had been reported previously including one gross deletion (c.722_2041del), one missense mutation (c.1764G>T), three non-sense mutations (c.194C>A, c.895C>T and c.1821G>A) and four invariant splice-site mutations (c.971+2T>C, c.1481+2T>A, c.1482-2A>G, c.1699-2A>G). Seven novel mutations were identified (c.373_441del, c. 504delG, c.537delC, c.851delA, c.1637G>A, c.1879T>C and c. 1482_1882 del). Ten of the eighteen mutations of BTK gene were located in the TK domain, four in the PH domain, three in the SH3 domain and one spanned the TH, SH3, SH2 and TK domain. Candidate genes of autosomal-recessive agammaglobulinemia, including IGHM, CD79a, CD79b and IGLL1, were screened in three patients without mutations in the BTK gene. A compound heterozygosity mutation in the IGHM gene (c.1956G>A, c.175_176insC) was identified in one patient. The results of our study further support that molecular genetic testing represents an important tool for early confirmed diagnosis of congenital agammaglobulinemia and may allow accurate carrier detection and prenatal diagnosis.

Changes of pituitary and penile structure in male adult rats following castration and high-fat diet

AIM

To investigate the influence of low androgen levels and high-fat diet on the structure of pituitary and penis in male rats.

METHODS

Ten-week-old adult male Sprague-Dawley rats were randomly divided into 2 groups, one fed a high-fat diet the other fed a normal diet; each group consisted of 3 subgroups: controls, castrated rats (with low androgen), and castrated rats given undecanoate replenishment. After 11 weeks, the structure of pituitary and penis were observed under light microscopy. Immunohistochemistry was used to assess the expression of FSH in pituitary and cyclooxygenase-2 (COX-2) in corpora cavernosa penis.

RESULTS

The structures of pituitary and penis in castrated rats were injured, and were more damaged in castration together with high-fat diet. Immunohistochemistry showed FSH expression in castrated rats pituitary while castrated rats on a high-fat diet had less positive staining than those on a normal diet. Vascular structure of corpora cavernosa penis, showed a strongly positive COX-2 expression in high-fat diet rats.

CONCLUSIONS

Castration and high-fat diet could induce structural damages of pituitary and penis in male rats. Replacement with testosterone could partially restore the impaired structure. The positive expression of COX-2 implied inflammatory pathway existence on vascular structure of penis in high-fat diet and low-androgen male rats.

Effects of Bonding Process Parameters on Wafer-to-Wafer Alignment Accuracy in Benzocyclobutene (BCB) Dielectric Wafer Bonding

Wafer-level three-dimensional (3D) integration is an emerging technology to increase the performance and functionality of integrated circuits (ICs). Aligned wafer-to-wafer bonding with dielectric polymer layers (e.g., benzocyclobutene (BCB)) is a promising approach for manufacturing of 3D ICs, with minimum bonding impact on the wafer-to-wafer alignment accuracy essential. In this paper we investigate the effects of thermal and mechanical bonding parameters on the achievable post-bonding wafer-to-wafer alignment accuracy for polymer wafer bonding with 200 mm diameter wafers. Our baseline wafer bonding process with softbaked BCB (∼35% cross-linked) has been modified to use partially cured (∼ 43% crosslinked) BCB. The partially cured BCB layer does not reflow during bonding, minimizing the impact of inhomogeneities in BCB reflow under compression and/or slight shear forces at the bonding interface. As a result, the non-uniformity of the BCB layer thickness after wafer bonding is less than 0.5% of the nominal layer thickness and the wafer shift relative to each other during the wafer bonding process is less than 1 μm (average) for 200 mm diameter wafers. The critical adhesion energy of a bonded wafer pair with the partially cured BCB wafer bonding process is similar to that with soft-baked BCB.

Determination of the width of the top quark

We extract the total width of the top quark, Γ(t), from the partial decay width Γ(t → Wb) measured using the t-channel cross section for single top-quark production and from the branching fraction B(t → Wb) measured in tt events using up to 2.3  fb(-1) of integrated luminosity collected by the D0 Collaboration at the Tevatron pp Collider. The result is Γ(t) = 1.99(-0.55)(+0.69)  GeV, which translates to a top-quark lifetime of τ(t) = (3.3(-0.9)(+1.3)) × 10(-25)   s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |V(tb')| < 0.63 at 95% C.L.

Detection of Pseudomonas syringae pv actinidiae in kiwifruit pollen samples

Presence of Pseudomonas syringae pv actinidiae (Psa) the causal agent of bacterial canker of kiwifruit in pollen samples collected from infected and non infected orchards in Italy and in New Zealand was determined by polymerase chain reaction (PCR) and by direct bacterial isolation Psa was isolated only from pollen samples collected in Italy including pollen collected from two uninfected orchards which the following year showed signs of infection Psa was also detected in pollen collected from male and female vines in an Italian infected orchard Pollen samples from Italy but not from New Zealand were collected with a vacuum device Psa could not be isolated from any of the 25 New Zealand pollen samples analysed This is the first report of Psa being associated with pollen There is currently no evidence that artificial pollination leads to increased infection or that pollen has been responsible for the introduction of Psa in a previously Psafree area

Prognosis and role of postmastectomy radiotherapy in patients with T1-T2 breast cancer with one to three positive axillary nodes

PURPOSE

To evaluate the prognosis and role of postmastectomy radiotherapy (PMRT) in T1-T2 breast cancer with one to three positive axillary nodes.

METHODS

The 10-year Kaplan-Meier locoregional recurrence (LRR), distant recurrence (DR), disease-free survival (DFS) and overall survival (OS) were compared between the NO and 1-3N+ cohorts. The role of PMRT was evaluated in the 1-3N+ cohort.

RESULTS

The 10-year LRR, DR, DFS, OS rates in NO and the 1-3N+ cohorts were as follows: LRR 7.5% vs 19.4% (p = 0.011); DR 14.4% vs 23.0% (p = 0.029); DFS 71.3% vs 51.2% (p = 0.001) and OS 77.0% vs 58.7% (p = 0.001). Of the 192 1-3N+ patients not treated and treated with PMRT, the outcomes were: LRR 20.1% vs 18.4% (p = 0.047); DR 26.4% vs 21.5% (p = 0.743); DFS 40.2% vs 55.4% (p = 0.260) and OS 40.7% vs 66.0% (p = 0.344), respectively.

CONCLUSION

PMRT reduces the 10-year LRR rate for such patients, but further examination is needed.

First Record of Bacterial Crown Rot of Papaya (Carica papaya) Caused by an Erwinia papayae-Like Bacterium in the Kingdom of Tonga

Symptoms resembling papaya bacterial crown rot (1,3) attributed to Erwinia papayae were first observed on 'Waimanalo' and 'Solo Sunrise' papaya on the island of Tongatapu, Kingdom of Tonga in July 2009. Spreading, dark green, water-soaked lesions formed on juvenile stem tissue and developed into a foul-smelling, wet rot that destroyed large sections of the stem. Coalescing, brown, angular, marginal, and intercostal lesions killed large areas of the lamina. Elongated lesions on petioles resulted in breakage and leaf death. Symptoms on stems typically moved toward the crown with the growing point being killed or the whole crown breaking off at a canker below. Isolations at 28°C on King's medium B (KB) yielded slow-growing, raised, white, mucoid colonies that produced a conspicuous, nondiffusable blue pigment in the medium. Two-day-old suspensions (1 × 10⁸ CFU/ml) of two cultures were injected into juvenile stem tissue, petioles, and laminae of four healthy papaya seedlings of 'Solo Sunrise' with a sterile 1-ml insulin syringe. Sterile water was used as a negative control. Typical water-soaked lesions appeared at all bacterial inoculation sites on all plants within 5 days but not on controls. Pigment-producing colonies similar to those used for inoculation were reisolated from four different stem lesions. Bacteria isolated from diseased tissues were gram negative, facultative anaerobes, oxidase negative, nonfluorescent on KB, induced a hypersensitive reaction on tobacco leaves, but could not cause soft rot on potato slices. Those characteristics, combined with blue pigment production, are consistent with the bacterium E. papayae. A partial sequence of the 16S rDNA gene of ~804 bp was amplified from four Tongan isolates (ICMP18248-18251) using primers 27f and 1492r (4). Sequences of these strains were 100% identical to each other (GenBank Nos. HQ286366-HQ286369), 99 and 98% identical to the 16SrDNA sequences of E. mallotivora strains LMG2708 (Z96084.1) and DSM4565 (AJ233414.1) respectively, and 97% identical to the 16SrDNA sequence of E. papayae strain NCPPB 4294 (AY131237.1). E. mallotivora and E. papayae cause different diseases, a leaf spot on Mallotus japonicus (2) and bacterial canker on papaya, respectively. They are closely related and in the laboratory are distinguished by only very few biochemical characteristics (1). E. papayae produces a blue pigment on KB and can utilize arabinose but not mannitol. E. mallotivora does not produce a blue pigment and can utilize mannitol but not arabinose. The four Tongan strains produced a blue pigment and could utilize mannitol and arabinose. Symptoms caused by the strains isolated from Tonga are typical of those caused by E. papayae and the strains identified share most of the characteristics of E. papayae. Because the Tongan strains were able to utilize mannitol as well as arabinose and their 16S rDNA was only 97% similar to E. papayae, these strains are referred to as an E. papayae-like bacterium. The taxonomic position of these isolates will be resolved with techniques such as Multilocus Sequence Typing analysis. To our knowledge, this is the first report of this highly destructive papaya disease in the Kingdom of Tonga and of a pathogen closely related to E. papaya in the country. References: (1) L. Gardan et al. Int. J. Syst. Bacteriol. 54:107, 2004. (2) M. Goto. Int. J. Syst. Bacteriol. 26:467, 1976. (3) N. H. Maktar et al. New Dis. Rep. 17:4, 2008. (4) F. Martin-Laurent et al. Appl. Environ. Microbiol. 67:2354, 2001.

Search for ZH → l+ l- bb production in 4.2 fb(-1) of pp collisions at sqrt[s] =1 .96 TeV

We present a search for the standard model Higgs boson produced in association with a Z boson in 4.2 fb(-1) of pp collisions, collected with the D0 detector at the Fermilab Tevatron at sqrt[s] =1 .96 TeV. Selected events contain one reconstructed Z → e+ e- or Z → μ+ μ- candidate and at least two jets, including at least one b-tagged jet. In the absence of an excess over the background expected from other standard model processes, limits on the ZH cross section multiplied by the branching ratios are set. The limit at M(H) = 115  GeV is a factor of 5.9 larger than the standard model prediction.

Epigenetic inactivation of T-box transcription factor 5, a novel tumor suppressor gene, is associated with colon cancer

T-box transcription factor 5 (TBX5) is a member of a phylogenetically conserved family of genes involved in the regulation of developmental processes. The function of TBX5 in cancer development is largely unclear. We identified that TBX5 was preferentially methylated in cancer using methylation-sensitive arbitrarily primed PCR. We aim to clarify the epigenetic inactivation, biological function and clinical significance of TBX5 in colon cancer. Promoter methylation was evaluated by combined bisulfite restriction analysis and bisulfite genomic sequencing. Cell proliferation was examined by cell viability assay and colony formation assay, apoptosis by flow cytometry and cell migration by wound-healing assay. TBX5 target genes were identified by cDNA microarray analysis. Cox regression model and log-rank test were used to identify independent predictors of prognosis. TBX5 was silenced or downregulated in 88% (7/8) colon cancer cell lines, but was expressed in normal colon tissues. Loss of gene expression was associated with promoter methylation. The biological function of TBX5 in human colon cancer cells was examined. Re-expression of TBX5 in silenced colon cancer cell lines suppressed colony formation (P<0.001), proliferation (P<0.001), migration and induced apoptosis (P<0.01). Induction of apoptosis was mediated through cross-talk of extrinsic apoptosis pathway, apoptotic BCL2-associated X protein and Granzyme A signaling cascades. TBX5 suppressed tumor cell proliferation and metastasis through the upregulation of cyclin-dependent kinase inhibitor 2A, metastasis suppressor 1 and downregulation of synuclein gamma and metastasis-associated protein 1 family member 2. TBX5 methylation was detected in 68% (71/105) of primary colon tumors. Multivariate analysis showed that patients with TBX5 methylation had a significantly poor overall survival (P=0.0007). In conclusion, we identified a novel functional tumor suppressor gene TBX5 inactivated by promoter methylation in colon cancer. Detection of methylated TBX5 may serve as a potential biomarker for the prognosis of this malignancy.

The electronic structure of epitaxially stabilized 5d perovskite Ca(1-x)Sr(x)IrO3 (x = 0, 0.5, and 1) thin films: the role of strong spin-orbit coupling

We have investigated the electronic structure of meta-stable perovskite Ca(1 - x)Sr(x)IrO(3)(x = 0, 0.5, and 1) thin films using transport measurements, optical spectroscopy, and first-principles calculations. We artificially fabricated the perovskite phase of Ca(1 - x)Sr(x)IrO(3), which has a hexagonal or post-perovskite crystal structure in bulk form, by growing epitaxial thin films on perovskite GdScO(3) substrates using an epi-stabilization technique. The transport properties of the perovskite Ca(1 - x)Sr(x)IrO(3) films systematically change from nearly insulating (or semi-metallic) for x = 0 to weakly metallic for x = 1. Due to the extended wavefunctions, 5d electrons are usually delocalized. However, the strong spin-orbit coupling in Ca(1 - x)Sr(x)IrO(3) results in the formation of effective total angular momentum J(eff) = 1/2 and 3/2 states, which puts Ca(1 - x)Sr(x)IrO(3) in the vicinity of a metal-insulator phase boundary. As a result, the electrical properties of the Ca(1 - x)Sr(x)IrO(3) films are found to be sensitive to x and strain.

Treatment of Symptomatic Intracranial Atherosclerotic Stenosis with a Normal-Sized Gateway™ Balloon and Wingspan™ Stent

The safety and performance of angioplasty using a normal-sized Gateway™ balloon and Wingspan™ stent for intracranial atherosclerotic stenosis were assessed. Seventy-two patients with intracranial stenosis (≥ 50%) were treated using an undersized (group U) or normal-sized (group N) Gateway™ balloon and a Wingspan™ stent. All patients were successfully stented. Stenosis improved from 74.2% before treatment to 23.8% immediately after treatment in group U and from 70.9% to 20.1% in group N. The two groups had similar rates of major periprocedural neurological complications (9.0% overall), none of which led to death. Residual stenosis at follow-up was 40.8% and 32.5% in groups U and N, respectively. In-stent re-stenosis (ISR) was significantly less frequent in group N (22.0%) than in group U (33.3%). It is concluded that use of a normal-sized Gateway™ balloon and Wingspan™ stent appears to be safe, to have a high rate of technical success, good immediate post-operative results and a low ISR rate.